For the record, I didn't downvote you.
Back to GP: The issue isn't that he's killing people, the issue is how boring he is to play against. Like I said, three options, get poked out of lane, farm with him while he assists his team and you don't, or have your base taken while he assists the team and you don't. It's just like old Shen.
Malphite: A champion shouldn't automatically win the lane if you don't directly counter them. Counter picks are important, but not picking one or even picking a bad champion into a lane shouldn't just automatically lose you the lane, ya know? Plus I don't see how three hit procs counter him considering he lowers attack speed.
Quinn: Come on, we're really saying CC as a counter is a thing? There's like three champions in this game that CC doesn't counter, Irelia, Olaf, and GP.
Rengar: If it were me, I'd change his ult to a global targeted ability that reveals the target and gives them the ! after the first 3/4/5 seconds, then give him an Eve-like stealth. This way it feels more like a hunter/hunted thing as opposed to 'lemme just reveal everything in the area, skirt around all those pesky tanks I can now see and go right to the target without them being able to do anything about it'. Now you can intercept him if he makes a mistake. Now there's risk.
Short of that, I'd get rid of his true sight and change it to regular sight, then make it so he can't cast spells midjump.
Renekton: For the millionth time, falling off late game is a myth. Lee Sin doesn't fall off late game, Shaco doesn't fall off late game, Renekton doesn't fall off late game. If they get fed, which they will with their early games, they will absolutely not fall off. No champion that gets fed falls off late game, these champions have better early game than most, so they'll most likely get fed. Also, Renekton's full combo is a bit obnoxious in terms of damage and the ability to do something about it.
Yasuo: Highly disagree. Shutting him down isn't nearly as easy as you make it out to be. It's the same situation with the ol' protect the kog'maw/vayne comps except these comps are loaded with knockups, and the target you have to kill is extremely mobile, has aoe cc, a shield that resets off of any knockup, and can three shot most tanks after ulting. On top of all that, he's got wind wall, which makes most mages/assassins much less of a threat.
Simply put, Yasuo decides whether he wins or loses. You do not outplay him, he fails to outplay you. If you both play perfectly, he wins. If he plays damn near perfectly and you play perfectly, he still wins.
Zed: Snowball assassin with great wave clear, poke, escapes, and no mana costs. He's going to get fed regardless of how safe you play. If he can't kill you solo in mid lane, he'll push the wave and roam bot lane. Simple solution: Make it so his passive can't be used on minions, make it so W cooldown starts after the shadow is swapped/disappears. Now Zed's farming isn't the easiest thing in the world and he has to make a decision whether or not he wants to use his shadow right away and lower the cd or keep it up and farm/harass from a distance.
I'm also going to add one more because I've been seeing it quite a bit lately and frankly, I'm surprised at how well it's doing. Devour
. This shit is just obnoxious.